Orthros

In the Byzantine Rite of the Eastern Orthodox Church and the Eastern Catholic Churches, Orthros (Greek (ὄρθρος, meaning "early dawn" or "daybreak") or Oútrenya (Slavonic Оўтреня) is the last of the four night offices, which also include vespers, compline, and midnight office. In traditional monasteries it is held daily so as to end at sunrise. In many parishes it is held only on Sundays and feast days. It is often called matins after the office it most nearly corresponds to in Western Christian churches.

Orthros is the longest and most complex of the daily cycle of services. It is normally held in the early morning, often — always in monasteries — preceded by the midnight office, and usually followed by the First Hour. On great feasts it is held as part of an all-night vigil commencing the evening before, combined with an augmented great vespers and the first hour. In the Russian tradition, an all-night vigil is celebrated every Saturday evening, typically abridged, however, in spite of its name, to as short as two hours. In the Greek parish tradition, orthros is normally held just before the beginning of the divine liturgy on Sunday and feast day mornings.

The akolouth (fixed portion of the service) is composed primarily of psalms and litanies. The sequences (variable parts) of matins are composed primarily of hymns and canons from the octoechos (an eight-tone cycle of hymns for each day of the week, covering eight weeks), and from the menaion (hymns for each calendar day of the year). During great lent and some of the period preceding it, some of the portions from the octoechos and menaion are replaced by hymns from the triodion and during the paschal season with material from the pentecostarion. On Sundays there is also a gospel reading and corresponding hymns from the eleven-part cycle of resurrectional gospels.

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